Title: A spherically symmetric black hole in a Dehnen dark matter halo
Abstract: While supermassive black holes (SMBHs) are primarily studied through their interaction with baryonic matter, their immersion within the central of galactic dark matter (DM) halos presents a unique and untapped physical laboratory. This talk provides a comprehensive overview of the theoretical predictions and observational prospects for using black hole to probe the fundamental nature of dark matter. In particular, we consider a static, spherically symmetric black hole solution surrounded by a Dehnen dark matter profile. The talk consists of three parts. First, we detail the construction of the solution and systematically investigate its geometric properties, including the horizon structure, scalar curvature invariants, and the energy conditions. Second, we examine the black hole's thermodynamics, quantifying the impact of the dark matter halo on its temperature and entropy. Finally, we probe the spacetime by analyzing null geodesics, revealing how the Dehnen profile modifies photon trajectories and potential observational signatures.
Date : 13th November 2025
Time: 01:00 P.M - 02:00 P.M
Abstract: In this talk, I will first review the derivation of the unitarity bound in a single-field inflationary model with small and rapid oscillatory potential. I will show that the revised unitarity cutoff of the model is somewhat higher than the naïve cutoff, 4 π f. Using this new cutoff, in contrast to the standard scenario where most of the observable information is encoded in the power spectrum, in this regime the oscillatory signal predominantly appears in higher-order correlation functions with large n. Finally, I will identify a phenomenologically relevant window in which n-point functions with 3 < n < 9 are potentially observable
Date : 28 August 2025
Time: 01:00 P.M - 02:00 P.M
Meeting Link: https://meet.google.com/vjs-pgwq-ros